At the cruising altitudes of modern commercial aircraft, the outside temperatures lie as low as −60° C. Liquids accumulated from the galley area or hand wash basins, as well as from the cargo compartment drain, cannot be discharged outboard without being heated first, namely because they would otherwise freeze immediately and form ice chunks such that the drain mast would be clogged. This is the reason why modern drain masts are heated.
Drain mast or drain systems according to the state of the art have the disadvantage, for example, that the heating of the liquid to be drained is associated with an increased energy demand. This additional energy needs to be generated by the on-board supply system. The additional heating elements provided in known drain systems may also lead to an increased space requirement.